UDS and DPM not the same

Ide · January 7, 2022, 11:37

Hi, I'm fairly new to Ansys, I'm trying to model airflow though a room like a ventilation system. I made 2 rooms with a slightly different configuration with the same inlet flow and same volume so I assumed that for both rooms the mean residence time should be equal as RD=V/Q. However, when I calculated the DPM and UDS for the residence time of both rooms they all were different. I only thought variance would change. My question is why can the mean residence time change along with the different rooms as well as methods of calculation.

LuckyTran · January 7, 2022, 11:53

If you have a labyrinth/maze then the residence time can be really really really long. Volume/volumetric-flow-rate is a zero-dimensional model that doesn't take shape into account.

January 7, 2022, 11:37	UDS and DPM not the same	#1
Ide New Member Ide Join Date: Jan 2022 Posts: 1 Rep Power: 0	Hi, I'm fairly new to Ansys, I'm trying to model airflow though a room like a ventilation system. I made 2 rooms with a slightly different configuration with the same inlet flow and same volume so I assumed that for both rooms the mean residence time should be equal as RD=V/Q. However, when I calculated the DPM and UDS for the residence time of both rooms they all were different. I only thought variance would change. My question is why can the mean residence time change along with the different rooms as well as methods of calculation.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Calculate UDS flux through the wall	ananth_01	FLUENT	0	August 5, 2013 08:33
UDS for droplet collection efficiency	mkozic	FLUENT	4	August 18, 2012 23:59
DPM and UDS	mighelone	FLUENT	0	June 3, 2011 08:27
How to apply Transport Equation on DPM Scalars?	yuhai	FLUENT	0	May 19, 2010 11:38
UDS source term	Umesh Shah	FLUENT	1	June 10, 2003 18:45

January 7, 2022, 11:53		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,845 Rep Power: 68	If you have a labyrinth/maze then the residence time can be really really really long. Volume/volumetric-flow-rate is a zero-dimensional model that doesn't take shape into account.